CVE-2021-28841 Explained : Impact and Mitigation

A Null Pointer Dereference vulnerability in TRENDnet TEW-755AP, TEW-755AP2KAC, TEW-821DAP2KAC, and TEW-825DAP devices could allow a remote attacker to cause a denial of service. Here's what you need to know about CVE-2021-28841.

Understanding CVE-2021-28841

This CVE involves a vulnerability in specific TRENDnet devices that could be exploited by a remote malicious user to disrupt services.

What is CVE-2021-28841?

The CVE-2021-28841 is a Null Pointer Dereference vulnerability present in TRENDnet TEW-755AP 1.11B03, TEW-755AP2KAC 1.11B03, TEW-821DAP2KAC 1.11B03, and TEW-825DAP 1.11B03 devices, allowing an attacker to trigger a denial of service by sending a specific type of request.

The Impact of CVE-2021-28841

If successfully exploited, this vulnerability could lead to a denial of service condition, potentially disrupting network services and causing inconvenience to users.

Technical Details of CVE-2021-28841

Below are the technical details regarding the vulnerability.

Vulnerability Description

The vulnerability arises from a Null Pointer Dereference issue when processing a POST request to apply_cgi via an action ping_test without a specific key, thus enabling the attacker to disrupt services.

Affected Systems and Versions

TRENDnet TEW-755AP 1.11B03, TEW-755AP2KAC 1.11B03, TEW-821DAP2KAC 1.11B03, and TEW-825DAP 1.11B03 devices are affected by this vulnerability.

Exploitation Mechanism

A remote malicious user could exploit the vulnerability by sending a POST request to apply_cgi via an action ping_test without including a required key, leading to a denial of service attack.

Mitigation and Prevention

To address CVE-2021-28841, consider the following mitigation strategies.

Immediate Steps to Take

Implement firewall rules to restrict access, monitor network traffic for suspicious activities, and apply patches recommended by TRENDnet promptly.

Long-Term Security Practices

Regularly update firmware, perform security assessments, conduct penetration testing, and educate users on cybersecurity best practices.

Patching and Updates

Stay informed about security advisories from TRENDnet, apply patches and firmware updates as soon as they are available to mitigate the risk of exploitation.